الواقع والحياد
13-09-2006, 12:18 AM
Nucleic Acids
Nucleic Acids are macromolecular structures which store and express all the information necessary for building and maintaining life.
DNA (DeoxyriboNucleic Acid) is considered as the repository of the genetic information.
RNAs (RiboNucleic Acids) may be regarded as vectors and translators of the information.
From a chemical point of view, Nucleic Acids are giant linear condensation polymers of Nucleotide sub-units.
A Nucleotide consists of
a nitrogenous base: purine (Adenine (A) or Guanine (G)) or pyrimidine (Cytosine (C) or Thymine (T) (or Uracil (U)in RNA
ِa sugar : Deoxyribose (DNA) or Ribose RNA
a phosphate group
A sugar and a base form a Nucleoside
A Nucleotide is a phosphorylated nucleoside
Inter-nucleotide linkages are formed by a phosphodiester bond between a 5'-phosphate group and the 3'-hydroxyl group of the next nucleotide sugar
The nucleotide sequence encodes the informations required for constructing proteins
http://www.geneticengineering.org/chemis/Chemis-NucleicAcid/Graphics/NucleicAcid.gif
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Nucleic Acids are macromolecular structures which store and express all the information necessary for building and maintaining life.
DNA (DeoxyriboNucleic Acid) is considered as the repository of the genetic information.
RNAs (RiboNucleic Acids) may be regarded as vectors and translators of the information.
From a chemical point of view, Nucleic Acids are giant linear condensation polymers of Nucleotide sub-units.
A Nucleotide consists of
a nitrogenous base: purine (Adenine (A) or Guanine (G)) or pyrimidine (Cytosine (C) or Thymine (T) (or Uracil (U)in RNA
ِa sugar : Deoxyribose (DNA) or Ribose RNA
a phosphate group
A sugar and a base form a Nucleoside
A Nucleotide is a phosphorylated nucleoside
Inter-nucleotide linkages are formed by a phosphodiester bond between a 5'-phosphate group and the 3'-hydroxyl group of the next nucleotide sugar
The nucleotide sequence encodes the informations required for constructing proteins
http://www.geneticengineering.org/chemis/Chemis-NucleicAcid/Graphics/NucleicAcid.gif
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